The present invention relates to an inlet guide vane device to control the flow and the pressure ratio of a centrifugal compressor or centrifugal compressor stage. More particularly, the present invention relates to an inlet guide vane that is adjustable to vary flow through the compressor or compressor stage.
Compressors, and more particularly centrifugal compressors, operate across a wide range of operating parameters. Variation of some of these parameters may produce undesirable efficiency and capacity variations. In addition, multi-stage compressors may operate under circumstances in which one or more of the stages operate at an undesirable pressure ratio or discharge too much or too little flow.